These barriers are not static, but dynamic, through time, even the "hard" ones that is, they change in shape and size and effectiveness through time, sometimes over long time periods and sometimes quite abruptly.
The survival rate of many implants diminishes (sometimes dramatically) over time.
I have lived long enough to realize that my views sometimes change over time.****** I've learned that it doesn't pay to go on the record with strong opinions: A. On topics that don't matter all that much, and, B. That are likely to evolve over time.
These freshly excavated soil mounds are easier to recognize than older nest entrances, which sometimes erode over time during periods of drought.
LQR answers qualitative questions about the lived experience of change, or sometimes stability, over time.
This finding is important, because it implies that other factors are more important when we try to explain why the retention of zinc phosphate cemented crowns sometimes fail over time.
The subfloor, the structural support below the top floor that you walk on, will sometimes shrink over time as the wood dries out, changing the shape slightly and resulting in high-pitched, irritating squeaks.
Such modeling is only possible with appropriate measurements, collected in observational studies, sometimes over extended time periods.
Villarreal's coach, sometimes over-excited schoolboy, other times a stern school master, seems to enjoy being contrary.
At the same time, outcomes are sometimes over-promised.
